55CrMnA Spring Steel

Material name: Spring steel
Grade: 55CrMnA
Standard: GB/T1222-2007

Features and scope of application:

55CrMnA spring steel has higher strength, ductility and toughness, better hardenability, lower sensitivity than manganese steel, less decarburization tendency than silicon-manganese steel, and greater temper brittleness. The outstanding advantages of 55CrMnA steel are good hardenability, hot workability, comprehensive mechanical properties, and anti-decarburization performance are also good for the production of heavy-duty, stress-stressed leaf springs and large diameter spiral springs in the vehicle and tractor industries.

Chemical Composition of 55CrMnA

C: 0.52~0.60
Si: 0.17~0.37
Mn: 0.65~0.95
S: ≤0.030
P: ≤0.030
Cr: 0.65~0.95
Ni: ≤0.35
Cu: ≤0.25
V: 0.10~0.20
55CrMnA Spring Steel Mechanical Property

Tensile strength σb (MPa): ≥ 1225 (125)
Conditional yield strength σ0.2 (MPa): ≥1080(110)
Elongation δ5 (%): ≥9 (for reference)
Area shrinkage ψ (%): ≥20
Hardness: hot rolling, ≤ 321HB;
Cold drawing + heat treatment, ≤ 321HB

55CrMnA Heat treatment specification:

Heat treatment specification: quenching 830~860 °C, oil cooling; tempering 460~510 °C.

55CrMnA Steel Corresponding to national brands

Corresponding to the US brand: G51550

Corresponding to Japanese brand: SUP9

Corresponding to the German brand: 55Cr3

Corresponding to the British brand: 525A58

Corresponding to the French brand: 55Cr3